Representative Jeff Roorda, of Barnhart, introduced the bill Friday in response to a Republican House member's proposal to jail lawmakers for introducing gun control measures.

Roorda says he was "inspired" by the GOP approach to protecting gun rights and he wants to do the same for unions. Rep. Mike Leara, of St. Louis County, is sponsoring the bill banning gun-control legislation.

Both measures would give lawmakers prison terms of up to four years for proposing gun restrictions or anti-union bills.

The Republican-led Legislature is currently working on proposals to curb collective bargaining by limiting the ability of unions to collect fees from employees' paychecks.